Users are increasingly performing tasks using remote computing resources, often referred to as part of “the cloud.” This has many advantages, as users do not have to purchase and maintain dedicated hardware and software, and instead can pay for only those resources that are needed at any given time, where those resources typically will be managed by a resource provider. Users can perform tasks such as storing data to various types of resources offered by a resource provider. In some instances, a process executing on behalf of a customer will attempt to write data to a data buffer in the system. If there is insufficient bounds checking, such that the data written exceeds the allocation, then the data can corrupt data value in memory addresses adjacent the destination buffer. If a system contains a buffer overflow condition in conjunction with processing untrusted data, then an adversary can attack the system with a buffer flow exploit.